// import { cookies, headers } from 'next/headers'
// import Negotiator from 'negotiator'
// import { match } from '@formatjs/intl-localematcher'

import { createInstance } from 'i18next';
import resourcesToBackend from 'i18next-resources-to-backend';
import { initReactI18next } from 'react-i18next/initReactI18next';
// import { i18n } from '.'
import type { Locale } from '.';

// https://locize.com/blog/next-13-app-dir-i18n/
const initI18next = async (lng: Locale, ns: string) => {
  const i18nInstance = createInstance();
  await i18nInstance
    .use(initReactI18next)
    .use(resourcesToBackend((language: string, namespace: string) => import(`./${language}/${namespace}.ts`)))
    .init({
      lng: lng === 'zh-Hans' ? 'zh-Hans' : lng,
      ns,
      fallbackLng: 'en-US',
    });
  return i18nInstance;
};

export async function useTranslation(lng: Locale, ns = '', options: Record<string, any> = {}) {
  const i18nextInstance = await initI18next(lng, ns);
  return {
    t: i18nextInstance.getFixedT(lng, ns, options.keyPrefix),
    i18n: i18nextInstance,
  };
}

// export const getLocaleOnServer = (): Locale => {
//   const locales: string[] = i18n.locales

//   let languages: string[] | undefined
//   // get locale from cookie
//   const localeCookie = cookies().get('locale')
//   languages = localeCookie?.value ? [localeCookie.value] : []

//   if (!languages.length) {
//     // Negotiator expects plain object so we need to transform headers
//     const negotiatorHeaders: Record<string, string> = {}
//     headers().forEach((value, key) => (negotiatorHeaders[key] = value))
//     // Use negotiator and intl-localematcher to get best locale
//     languages = new Negotiator({ headers: negotiatorHeaders }).languages()
//   }

//   // Validate languages
//   if (!Array.isArray(languages) || languages.length === 0 || !languages.every(lang => typeof lang === 'string' && /^[\w-]+$/.test(lang))) {
//     console.error(`Invalid languages: ${languages}`)
//     languages = [i18n.defaultLocale]
//   }

//   // match locale
//   const matchedLocale = match(languages, locales, i18n.defaultLocale) as Locale
//   return matchedLocale
// }
